Valve operating mechanism of internal combustion engines



May 19, 1931. J. GARDNER ET AL 1,805,578-

VALVE OPERATING MECHANISM OF INTERNAL COMBUSTION ENGINES 3 Filed Aug. 50. 1929 2 Sheets-Sheet.- 1 f Fig2 / NVGNTMZ.

' A WW M y 1931. J. GARDNER ET AL 1,805,578

VALVE OPERATING MECHANI SM Ol fINTBRNAL COMBUSTION ENGINES Filed Aug. 30. 1929 2 Sheets-Sheet 2 Fig.3

Patented May 19, 1 931 UNITED f STATES JOSE-PH GARDNER AND JOSEPH rruensrorr ciinnivjninj onnsrE-n, ENGLAND, assrenons To" 1... Gennitnnj r NEAR MANCHESTER, ENGLAND, A 'BnITIsrrfooMranY VALVE OPERATING ivrncrmmsiu"orfriifirrirtireifibdilrnfisrron Application filed August so, 1929, Serial no. ssez issxairairn{creatismarnimaear 4, 1e29.

Thisinvention relates to internal combustion engines of the compression ignition type. It is usual to time the inlet valves of such engines so that they close considerably after 5 the end of the suction stroke'and fornormal running conditions this arrangement has advantagesbut at starting when the engine is.

turned at a comparatively low rate usually by compressed air, the late closing of the inlet valve reduces the effective compression ratio and therefore the compression pressure and the compression temperature.

It is known to vary the timing of the inlet valve operating cam relatively to the engine tory drawings Figure 1 is an elevation witha part in sec tion, Figure 2 asectional elevationjat right angles to Figure 1, and Figure 3 a plan view with the cover removed, of inlet valve oper ating means constructed and arranged in one convenient form in accordance with our invention. V

Figure 4 is a detail view illustrating the end of the valve rocker which engages the I inlet valve stem. v

- the usual push rod 0, with two faces (Z, a;

The same reference letters in the differentviews indicate the same parts. V

We arrange the rocker a which operates the inlet valve 1) and which is itself operated by either of which can be caused to engage the valve stem by a suitable lateral displacement of the rocker along 1 its shaft 7 against the pressure of the springg. The operative face cl of the rocker provides for a minimum clearance between the valve stem 0 and itself and is for normal running conditions with the inlet valve closing, considerably after the end of the suction stroke, whilstthe operative face =tion? of the spindle which'isnot cut} away be eiprovides fora relativelyjconsiderabietlear- 'ance so that} the inlet valve '6 opens iwla ter "and closes, earlier. I -'-I;helateral inovementjof th'egrocker a is; eifectedby a scroll or facecarn' h wh ch e gagese i i e "o t e. o r at .and is operated by a handleqf'upon a; spindle carr ymgsuch 'facec'am. 1

y :rhe spindle a, carrying said as eam h V and handle is cutaway-at two points at, i so that ;when-thef handley' is turned to bring either of said out 'away'portionsbeneath-the rocker a, the rocker? can move; to its tull -e2;-

tent as determined hy the *push rod 0, but whenwtheshaft 1c is turned to bringthe {porneath the rocker, thedattferjsprevented-{gem following up the puishxrodfc zas it 'is' withdr WIl;TF@1 O fih l ja r to ri e; "S valve 'istherefore held open and acts as a compression relief means. of the operating handle shown at X, Figure 2, the cam 72; is clear of the rocker a and the cut away portion m of the spindle h is be-' neaththe rocker so that the latter operates the valve in a'normal manner; in a second position as indicated at Y, Figure 2, the face cam in is still clear of the rocker but the spindie is is preventing the rocker from moving to its full extent to closethe valve bthis is... the compression relief position; in the third;

position of the handle shown at Z, Figure 2,

the face cam h has moved the rocker to bring the end e into operation and the cut away portion n of the spindle is is beneath the rocker athis is the starting position. v

Our improvement is particularly advantageous for use with high speed engines of the compression ignition type.

What we claim is 1. In internal combustion engines of the compression ignition type, the combination.

with the inlet valve, of a rocker arm having two operative faces for engaging the valve stem,.one face leaving a relatively consider able clearance between itself and the valve scroll cam fortraversing said arm axially along said shaft to bring one or other of said faces into operation, a spring around the shaft opposing said traversing movement, 100 7 In the position f stem, a shaft carrying'said rocker'arm, a

and meansv for limiting the movement of the rocker arm in a direction to allow of the closure of the inlet valve.

2. In internal combustion engines of the compression ignition type, the combination with each inlet valve of a rocker arm for operating said valve having two operative faces side by side for engaging the valve stein, one face leaving a relative considerable clearance between itself anci the valve stem, a shaft carrying said rocker arm, a spring around said shaft holdin the rocker arm in a position in which the ace thereof leaving a minimum working clearance between itself and the valve stem is in service, a spindle, a scroll or face cam upon said spindle adapted to engage said rocker arm and move it axially along its shaft to bring into service the face with a considerable clearance between itself and the valve stem, the said spindle being shaped either to obstruct the movement of the rocker arm in a direction which allows of the closure of the inlet valve or to clear such arm, and a handle upon said s indle adapted in one position to a low one ace of the rocker arm to be in service, in another position to cause the other face to be in service and in a third position to revent the closure of the inlet valve.

11 testimony whereof we have signed our names to this specification.

JOSEPH GARDNER.

JOSEPH HUGH STOTT GARDNER. 

